Lincoln Impringer Conveyor Oven 1200 - Manual (Page 33)

Impinger I -–1000 Series Service Manual - International 33
Intermittent heating As Follows Both the main fan motor and burner blower motor
are equipped with thermal protection and will cease
to operate if overheating occurs. This can cause
the units to cycle on and off intermittently. This may
be caused by improper ventilation. Also most of the
problems listed under "oven will not heat" can
cause intermittent failure.
Voltage Supply Check incoming voltage supply at line 1 to neutral.
There should be a voltage reading of 120 VAC. If
not present, check breakers.
3 Amp Fuse This conveyor fuse is located on the front panel.
Replace if defective.
Fuse Holder Conveyor Switch Check and/or Replace. Same procedure as for fan
switch.
D. C. Motor Control Board Check for 120 VAC input to D. C. control board
across L1 and L2. Check the 3 amp fuse on the D.
C control board. Check for D.C. voltage at terminal
F1 and F2. Voltage should be 100 VDC ± 10
steady. If this voltage is not present, replace D. C.
control board. Check for D. C. voltage output to the
motor across terminals A1 and A2 (this voltage
should be approx. 125 VDC at maximum conveyor
motor speed).
Speed Control Potentiometer This is a 0 to 400 ohm or 0 to 500 ohm, 10-turn
potentiometer. WITH POWER OFF: remove the
red, white, and black leads from terminals S1, S2,
S3. With a digital multimeter, check the ohm
reading across the red to black leads. This ohm
reading should be a steady 400-ohm, or 500-ohm,
through the entire 10-turn rotation of the
potentiometer. Red to white, should be 0-400 or 0-
500 ohms as the pot. is rotated. Check for shorts or
opens or unsteady, ohm reading, if potentiometer is
defective, replace. If the potentiometer checks OK,
and
there is no output at terminals A1 and A2, replace
the D.C. control board.
Reversing Switch If there is D. C. voltage output from the motor
control board, but the conveyor drive motor is not
running, check the D.P.D.T. reversing switch.
Conveyor will not run
(S/N 100-4389)
Conveyor Drive Motor Check the conveyor drive sprocket for tightness.
Disconnect the motor, check the red and black
motor leads for opens, shorts or grounds. Check
the brushes for excessive or
abnormal wear.
Replace as needed. Reconnect motor. Test for
operation. If motor does not run, replace.
Voltage Supply Check incoming voltage supply at line 1 to neutral.
There should be a voltage reading of 120 VAC. If
not present, check breakers.
3 Amp Fuse This conveyor fuse is located on the front panel.
Replace if defective.
Fuseholder Check and/or Replace
Fan Switch See procedure for checking on page 26.
Conveyor will not run
(S/N 4390 to Q14974
1000 Series
S/N 4390-Q14790
1200 Series)
Conveyor Switch Same procedure as for fan switch.
NOTE: (Dual Belt Ovens) Dual belt ovens utilize 2 complete independent
conveyor drive systems. The trouble shooting
procedures are the same as single belt ovens,
except that the dual belt ovens use one each of the
following: one "A" DC. control board and one "B" D.
C. control board.